Pressure forming apparatus in paper making including a suction cylinder mold



p 3, 1966 M. F. HAYES ETAL PRESSURE FORMING APPARATUS IN PAPER MAKINGINCLUDING A SUCTION CYLINDER MOLD 5 Sheets-Sheet. 1

Filed Jan. 20, 1964 INVENTORS Mldrd E Hayes 22 ORNEYS & Robert/VI HayasSept. 13, 1966 M. F. HAYES ETAL 3,272,692

PRESSURE FORMING APPARATUS IN PAPER MAKING INCLUDING A SUCTION CYLINDERMOLD Filed Jan. 20, 1964 5 Sheets-Sheet INVENTORS Malian; FT/lqyes &Ruberi M Hayes M16MW 22% TTORNEYzS' p 3, 1966 M. F. HAYES ETAL 3,272,692

PRESSURE FORMING APPARATUS IN PAPER MAKING INCLUDING A SUCTION CYLINDERMOLD Filed Jan. 20, 1964 5 shehs Sheet I5 v H a H 1 I. r H! area/ 0INVENTORS Mallard f-T Hayes & Raberfi flih ayes 5r (27W,%M M

United States Patent 3,272,692 PRESSURE FORMING APPARATUS IN PAPERMAKING INCLUDING A SUCTIUN CYLIN- DER MOLD Millard F. Hayes and RobertM. Hayes, both of R0. Box 92, Hudson Falls, NY. Filed Jan. 20, 1964,Ser. No. 339,011 Claims. (Cl. 162-4517) This invention relates to papermanufacture, and more particularly to suction rolls for use in suchmanufacture.

In order to remove water from paper during its manufacture, severaldifferent kinds of suction rolls are employed. For instance, in aFourdrinier apparatus, the wire upon which the sheet of paper is formedis generally transported around a suction couch roll from which thepaper is transferred to the felt. The suction supplied by such a roll isoperative not only to remove water from the sheet of paper, but also topull the fibers of the paper sheet together, so that it can betransferred to the felt at high speed.

The present invention is applicable for use in suction rolls employed atvarious points in paper manufacture, and for example in the suctioncouch roll of the Fourdrinier apparatus. However, the invention isparticularly applicable, and will be described herein, in conjunctionwith a cylinder mold upon which a sheet of paper is formed from a stockof paper fibers entrained in water. Such a mold conventionally comprisesa cylindrical wire mesh called a face and which is supported by a pairof end spiders and a plurality of intermediate spiders which themselvesmount arcuately-spaced supporting rods. A winding wire is wound undertension on the rods to form a supporting framework for the wire mesh,which may either be of a single layer or of two different layers ofdifferent mesh size. In operation of the cylinder mold, the stock isdelivered from outside of the roll at a speed generally corresponding tothe peripheral speed of the roll and flows through the face into theinner part of the roll. During its flow through the face, nearly all ofthe fibers entrained in the stock are held by the outside surface of theface and together form the paper sheet.

In the past most cylinder molds have operated with the roll immersed ina slurry of water carrying fibers entrained therein. This immersion inthe slurry, together with the centrifugal forces operating upon thestock during rotation of the roll, interfere with the most efficient andrapid formation of the paper sheet.

To reduce these disadvantages of cylinder molds, it has been proposedthat suction be applied internally of the mesh face so as to build up agreater head tending to remove more water from the paper fibers and toallow the sheet to be formed faster. One way in which this has been donein the past is through sealing of the ends of the cylindrical roll andpulling a vacuum by a pipe connected to the end seal of the cylinderroll. With this method, however, it is very difficult to generate anyconsiderable vacuum, since a large portion of the cylinder mold isexposed to atmosphere. Moreover, the cylinder mold still rotates in thewhite water, or slurry with the disadvantage pointed out above.

Other solutions to the problem of application of a vacuum to cylindermolds employ perforated solid castings in conjunction with mesh faces,for the cylindrical surface of the rolls. Such castings are of coursemuch thicker than the mesh faces and are capable of supportingthemselves, so that supporting spiders, rods and winding wires are notrequired. In one of these prior art vacuum molds, vacuum is applied tothree-quarters of the arcuate portion of the mold which is either underwater or covered by the wet sheet of paper, and the fourth quadrant,which is exposed to air, is sealed off from the rest of the surface.

3,272,692 Patented Sept. 13, 1966 ice In another mold of this generaltype, suction boxes are employed to apply vacuum to the inner surface ofthe quadrant of the casting which is instantaneously approaching thecouch roll.

These last two prior art suggestions suffer not only from thedisadvantage of having half of the mold under water and thereby subjectto turbulence interfering with proper sheet formation, but also from theincreased effect of centrifugal force resultant from the thickness ofthe slugs of water which pass through the holes in the castings. Theimportance of the latter feature may be appreciated if it is consideredthat the castings may be conventionally of the order of 1% inch inthickness, with each perforation therethrough of approximately inchdiameter. The size of the slugs or solid cylinders of water subject tocentrifugal force during rotation of the mold is of course tremendouslyhigher than the size of the droplets passing through a wire mesh facewhich may be of the order of 5080 mesh.

The present invention avoids the disadvantages of the prior artsolutions to the problem of drawing a vacuum on a cylinder roll byretention of the conventional mesh face design and the application of avacuum to a portion of the periphery of the face through watercollectors connected to a central core about which the mounting spidersand face of the cylinder are rotatable.

In particular, the present invention replaces the conventional hollowrotatable shaft upon which the spiders are mounted for rotationtherewith by a hollow stationary core upon which the spiders, and hencethe face are rotatably mounted. This core has slots extending from itsouter surface into its inner chamber, which slots mate with Watercollectors having funnel portions which define passages extending fromadjacent the inner surface of the portion of the face to which stock issupplied, to the core slots. An air pump is connected to this corechamber to increase the head across the face and thereby increase thespeed and otherwise improve the formation of the paper sheet.

The invention will now be more fully described in conjunction withdrawings showing a preferred embodiment thereof.

In the drawings:

FIG. 1 is a cross-sectional view of the cylinder mold of the invention;

FIG. 2 is a sectional view taken along line 2-2 of FIG. 1;

FIG. 3 is a partial sectional view similar to FIG. 1 of a modificationof the apparatus of FIGS. 1 and 2; and

FIG. 4 is a diagrammatic view of the water and air connections to thecylinder mold of the preceding figures.

Referring first to FIGS. 1 and 2, a cylinder mold conventionallycomprises a wire mesh face 10 Which consists of a mutiplicity of smalldiameter wires which are spaced close together but which form openingstherebetween through which water can pass. The outermost layer or faceof the cylinder roll is conventionally of between 50 and mesh (wires perinch), depending upon the type of paper to be made. This face issupported, either directly or with an intermediate coarser mesh, by awinding wire 11 which is wrapped regularly around a number of supportingrods 12. The rods 12 are in turn supported by a pair of end spiders 13and 14 to which opposite ends of the rods are fixed and a plurality ofintermediate spiders 15. The intermediate spiders preferably havesemi-circular notches formed in their radially outermost surfaces, tohold the rods against forces tending to push them inwardly.

A common illustrative embodiment of the cylinder roll might be of 36inch outside diameter with 1087 inch diameter rods 12 supporting an 8gauge winding wire 11 notched into the supporting rods half theirdiameter, and

with the spiders 4 /2 inches apart. It might also be desirable tosupport the face by an inner wire mesh or cloth which is considerablymore coarse and might be of the order of 14 mesh, to prevent the facefrom being forced into the spaces between winding wire.

Stock, which consists of fibers entrained in water on the order of 1part in 200, is delivered to one quadrant of the cylinder mold through achannel partially defined by the upper plate and the lower plate 21(FIG. 1). The lower plate may be provided with a sealing member 22 whichbears against the surface of the face 10 to restrict the area of theface to which stock is delivered. It is conventional to increase thespeed of flow of the stock as it approaches more closely to the face, sothat its velocity will be approximately the same as the peripheral speedof the cylinder roll when the stock strikes the face. For this purpose,the stock is conventionally directed substantially tangentially of theroll in a channel of gradually decreasing size, as indicated in FIG. 1.

The apparatus so far described is a known type of cylinder machine.However, such machine also includes a shaft upon which the spiders aremounted and which is rotated with such spiders. Though the shaft isconventionally hollow, the central chamber of such shaft is not normallyused for any purpose.

In contrast, with the apparatus of the present invention, rather thanrotating the shaft with the spiders and the face, the spiders arethemselves mounted on a central stationary hollow cylindrical core 25.As will be seen particularly in FIG. 2, the spiders are rotatablysupported on the central core by fiber washers 26 which are preferablywater-lubricated, as through slots 26', into the fiber washers throughthe wall of the central core.

The core is also provided with a plurality of slots 27 which extendthrough its wall into the inner chamber 28. These slots, as shownparticularly in FIG. 1 are of generally arcuate shape corresponding inposition generally to that of the area of the face to which stock isdelivered. As shown in FIG. 2 the slots 27 are of relatively short axialextent, with one slot between each pair of supporting spiders.

These slots 27 mate with passages 29 of generally funnel-shape which areformed by water collectors 30. The water collectors each comprise a ringportion 31 which encircles the core 25 and which is clamped to the coreby a conventional type of clamping means shown at 32, and a funnelportion 33 which extends radially outward from the ring portion towardthe face 10 of the cylinder. The outermost portion of the funnel portionof each water collector has wall surfaces 34 and 35 (FIG. 1) which arespaced apart by a distance greater than the separation between the edgesof the channel formed by plates 20 and 21, through which stock isdelivered to the cylinder.

The wall portion 35 is provided with a sealing member 36 which, like themember 22, may be of hard rubber, and which extends to a positionimmediately adjacent the rods 12, or may even contact such rods to rubthereagainst during rotation of the cylinder. In similar fashion, thewall portion 34 of the funnel-shaped water collector is supplied with asimilar type of sealing member 37 which extends outwardly therefrom andwhich preferably contacts the rods during rotation of the cylinder.Alternatively, this sealing member, like the member 36, may terminatejust inward of the rods so that there is no abrasive contact duringrotation of the cylinder.

It will be seen that the arcuate portion or quadrant of the periphery ofthe roll which is delimited by the wall portions 34 and may be dividedinto two parts. The first part is that to which stock is supplied, andthe second part is a portion in advance of the stock entrance segmentand which is exposed only to air.

Referring again to FIGS. 1 and 2, it will be seen that the remainingouter wall portions of each water collector 30, namely thoseaxially-separated portions identified at 40 and 41, are positionedimmediately adjacent the surfaces of spiders 15. In fact, the spiders 15have a section of reduced thickness forming ribs 42 which separate theadjacent wall portions 40 and 41 of adjacent water collectors 30. Thespiders themselves are of generally arrow-shaped cross section, with ahead portion 43 extending radially outward from the rib portion 42. Thishead portion comes nearly to a point, so that the face 10 is notshielded by the spiders to any substantial extent.

As a result of this construction of the spiders and the watercollectors, substantially the entire axial extent of the face is coveredby the openings defined by the wall portions 34-35, and 4041, of thewater collectors 30.

As shown, particularly in FIGS. 1, 2 and 4, the cylinder machineincludes, in addition to the parts so far described, a vat 50 withinwhich the cylinder machine is mounted for rotation, and to which thestock is supplied for formation of the paper sheet on the face 10. Theopposite ends of the cylinder are sealed with respect to the walls 51and 52 of the vat, as by fiber bearing rings shown at 53 and 54 in FIG.2 and which each have an internal channel within which a sealing O-ring55 is mounted. Of course the opposite end spiders 13 and 14 rotate withrespect to the vat walls 51 and 52, but the sealing structure abovedescribed prevents leakage of the stock or of air between these parts.

One end portion 57 of the central core 25 is sealed off, but the otherportion is connected to a T connector 58 which has upper and lowerdischarge openings 59 and 60 designed to be connected to appropriatepipes. As indicated diagrammatically in FIG. 4, the upper flange 59 isconnected to the suction side of an air pump or fan shown at 61. Thisfan is capable of supplying enough of a negative pressure that an addedhead of the order of, e.g. 17 or 18 inches of water is provided acrossthe face of the cylinder machine. This head adds to the hydraulic headof 6 to 7 inches of water which is normally employed in cylinder moldmachines, to encourage both water and air to pass through the face 10 ofthe cylinder and into the funnel-like passages 29 provided by the watercollectors 30. The water and air then pass through the slots 27 into thechamber 28 in the central stationary core 25. The water is then directedout through the opening 60 into an appropriate white water collectorschematically indicated at 62 in FIG. 4. As indicated above, the air ofcourse fiows to the suction side of the pump 61 through the opening 59.

As also indicated in FIG. 4 additional stock may be added to the whitewater discharged into the collector 62, such additional stock being ofgreater concentration of fibers than the stock supplied to vat 50, inorder that the combination of the white water discharge and the addedstock will bring the discharge of collector 62 back to the consistencyof stock which should be supplied to the vat 50. As indicated, a pump 63may be provided to supply the appropriate hydraulic head to force thestock into the passage shown in FIG. 1 as defined by the plates 20 and21.

As is conventional in cylinder machines and :as shown in FIG. 1, thepaper sheet which is formed by passage of the white water through theface 10 of the cylinder roll is transferred to a felt generally shown at70. This felt contacts and drives a couch roll 71 of conventionaldesign. Since the felt is in contact with the cylinder, the cylinder isdriven in the same direction as the felt to cause transfer of the formedsheet from the face 10 to the felt 70.

The felt and couch roll 71 need not be further described because theyare of conventional and well known form and purpose. It will be evident,however, that with the apparatus of FIGS. 1, 2 and 4, the stock isdelivered to a portion of the periphery of the face 10 which is of lesscircumferential extent than the distance between the seal members 36 and37 on water collector wall portions 34 and 35. As a result, onlymoisture from the formed paper sheet and air is drawn through the facefrom the portion of that sheet between the sealing member 37 and theforward end of the stock passage. This tends to consolidate the fibersof the sheet, as well as to reduce the moisture content thereof, so thatthe sheet may more easily 'be transferred at high speed to the felt 7 0.

Since the quadrant of the cylinder roll upon which the paper sheet isformed is in effect divided into a part through which water is drawn anda part through which air is drawn, it is possible to completely isolatethese two portions and to supply a different or stronger vacuum for thesecond portion. This approach is illustrated diagrammatically in FIG. 3wherein the air-portion is isolated from the water-portion by a sealingmember 75 forming an extension of a further wall portion 76 of the watercollector. The wall portion 76 in turn is connected to a ring portion 77surrounding a pipe 78. An appropriate passage into the pipe 78 may beprovided such that, with a different air pump or fan connected to suchpipe, a greater amount of negative pressure may be supplied to the innersurface of the face between the sealing members 37 and 75, and thedegree of compression and drainage of the sheet in this area may beincreased.

It will be evident that, particularly with larger cylinders, more thantwo chambers or funnel passages could be provided, and more than twodifferent suction pressures could be supplied.

Though the cylinder machine of the drawings has been illustrated asdriven by the felt and couch roll, it will be evident that the cylindercould be directly driven, as for instance by providing the cylinder witha flange upon which a gear is mounted and by driving that gear throughconventional motive means.

As was indicated earlier, this invention is particularly applicable touse with cylinder molds, but it is not limited to such use, being infact of utility whenever it is desired to employ a perforate face ofsmall thickness, with supporting spiders, yet a moderate vacuum isdesired to be applied to the face, for the withdrawal of moisture frompaper.

It will be evident that many minor changes could be made in theapparatus specifically described herein without departure from the scopeof the invention. The invention therefore is not be considered limitedto the preferred embodiment disclosed but rather only by the scope ofthe appended claims.

We claim:

1. Apparatus including a suction roll, for use in paper manufacture, andwhich comprises a long cylindrical central hollow stationary coreforming an axis for the roll,

a pair of end spiders and a plurality of intermediate spiders eachrotatably mounted on said core and spaced apart axially therealong,

a wire mesh face of cylindrical shape mounted on said spiders forrotation therewith about said core and forming a porous cylindricalcovering for the roll to support paper fibers traveling in the directionof rotation of the roll, along an are extending part way around theperiphery thereof,

said core having a plurality of slots each extending between an adjacentpair of spiders and through the wall of the core into its centralchamber,

a different water collector mating with each of said slots and extendingradially outward therefrom, each said collector defining an inner airand water passage extending from adjacent the inner surface of the faceto its respective said slot,

an air pump connected to said central chamber to pump air therefrom sothat air and water are pulled through said mesh face into the chamber ofsaid core,

and means for discharging the air and water from said chamber.

2. The apparatus of claim 1 including a plurality of supporting rodscoaxial with said core, fixed at their opposite ends to said end spidersand supported intermediate their ends by said intermediate spiders, saidrods being spaced apart circumferentially of the spiders to form asupporting framework,

and winding wire wound about the framework of said rods with eachwrapping thereof spaced from its adjacent wrapping, said winding wireforming a support for said mesh face.

3. The apparatus of claim 2 in which said water collectors each comprisea sleeve portion encircling and clamped to said core with an openingthrough said sleeve portion aligned with its respective slot in saidcore,

and a funnel portion extending radially outward from the sleeve portionand defining said air and water passage.

4. The apparatus of claim 3 in which said funnel portion of each watercollector defines an axially-extending opening of substantially the samelength as the distance between its next adjacent spiders so thatsubstantially the entire axial extent of a partial circumferentialportion of said face is opposite said openings and is therefore exposedto negative air pressure such as to pull water through said face frompaper extending along that portion of its outer surface.

5. The apparatus of claim 4 in which said funnel portion of each watercollector extends circumferentially in a direction perpendicular to theaxis of the roll for only a limited extent and further including sealmembers mounted at the circumferentially-opposite sides of each saidwater collector, said seal members each extending axially substantiallythe entire distance between adjacent spiders and outwardly into closeproximity to said mesh face, whereby water is pulled through only alimited circumferential sector of the face during each moment.

6. In apparatus including a cylinder mold for forming a sheet of paperfrom a stock of paper fibers entrained in water and which comprises aroll composed of a pair of end spiders and a plurality of intermediatespiders sup porting a plurality of axially-extending, arcuately-spacedsupporting rods on which is wound a winding wire forming a supportingframework for a wire mesh face; means defining a passageway fordelivering stock at approximately the speed of the roll to acircumferentially-limited portion of the periphery thereof, and a movingfelt in contact with a portion of the periphery of the rollcircumferentially displaced from said limited portion thereof in thedirection of movement thereof, to rotate the roll and remove the sheettherefrom;

the improvement comprising a central stationary hollow cylindrical coresupporting said spiders to permit rotation of the roll with respect tothe core and having axially-spaced slots into its central chamber fromits outer periphery, said slots being positioned each between adifferent pair of adjacent spiders,

a different water collector mating with each of said slots and mountedon and fixed to said central core, each collector defining an inner airand water passage extending from adjacent the inner surface of the faceto its respective slot,

an air pump connected to said central chamber to pump air therefrom sothat air and water are pulled through said mesh face into the chamber ofsaid core,

and means for discharging air and water from said chamber.

7. The apparatus of claim 6 in which said intermediate spiders are ofrelatively short axial extent in the radially outermost portion thereof,so that only small portions of the face are shielded thereby,

and said water collectors each include a funnel-like member extendingradially inward from adjacent the inner surface of the face to the coreand having wall portions defining said passage, the outermost surfacesof said wall portions defining an opening of size at least coextensiveand aligned with the portion of said circumferentially-limited peripheryof the roll to which stock is delivered between the spiders adjacentthereto, said water collectors being operable to carry away all waterwhich passes through said face, whereby the roll does not rotate in apath of white water, so as to avoid interference with sheet formationthereon.

8. The apparatus of claim 7 in which said discharging means comprises aT-shaped connection to one end of said core chamber,

the other end being closed, with the head of the T extending verticallyand the body thereof connected to the chamber,

and pipe means connecting the upper end of the head portion of the T tothe suction side of said air pump, water being discharged through thelower end of the head portion of the T.

9. The apparatus of claim 8 in which each water collector has a sealmember mounted at the circumferentiallyopposite sides of the wallsdefining the said opening, said seal members each extending axiallysubstantially the entire distance between the adjacent spiders andoutwardly into at least close proximity to the mesh face.

10. The apparatus of claim 9 in which the circumferential spacingbetween the seal members of each water collector is substantiallygreater than the circumferential extent to which stock is delivered.

References Cited by the Examiner Sievers 162-369 DONALL H. SYLVESTER,Primary Examiner. S. LEON BASHORE, Examiner.

1. APPARATUS INCLUDING A SUCTION ROLL, FOR USE IN PAPER MANUFACTURE, ANDWHICH COMPRISES A LONG CYLINDRICAL CENTRAL HOLLOW STATIONARY COREFORMING AN AXIS FOR THE ROLL, A PAIR OF END SPIDERS AND A PLURALITY OFINTERMEDIATE SPIDERS EACH ROTABALY MOUNTED ON SAID CORE AND SPACED APARTAXIALLY THERELONG, A WIRE MESH FACE OF CYLINDRICAL SHAPE MOUNTED ON SAIDSPIDERS FOR ROTATION THEREWITH ABOUT SAID CORE AND FORMING A POROUSCYLINDRICAL COVERING FOR THE ROLL TO SUPPORT PAPER FIBERS TRAVELING INTHE DIRECTION OF ROTATION OF THE ROLL, ALONG AN ARE EXTENDING PART WAYAROUND THE PERIPHERY THEREOF,